The recent outbreaks of bacterial based diseases arising from the ingestion of meat or poultry products have underscored the need to refrigerate these products as soon as possible in the processing and distribution process. One method for quickly chilling such products is to immerse the product in water at or near 0.degree. C. The water used for this purpose is pumped from a refrigerated tank into an immersion tank containing the products to be chilled. The spent water from the immersion tank is returned to the refrigerated tank to be re-cooled.
While this arrangement reduces the time at which the food products remain at an elevated temperature, it introduces a new source of possible contamination, namely the water from the refrigerated tank. The water collects micro-organisms from the food products. This contamination increases with time. To prevent contamination of the food products subsequently treated, some form of sterilization system is needed to assure that any micro-organisms that enter the water stream are killed.
One method for sterilizing the chiller water is to introduce a sterilizing agent such as chlorine gas or mixed oxidants of the type described in U.S. Pat. No. 5,316,740 into the water. However, the concentration of such agents must be maintained within strict limits. If too much of the agent is added, the taste of the food products will be adversely affected. If too little agent is added, the biological contamination will not be destroyed.
Broadly, it is the object of the present invention to provide an improved chilled water system for rapidly cooling food stuffs.
It is a further object of the present invention to provide a chilled water system in which the concentration of a sterilizing agent can be controlled.
These and other objects of the present invention will become apparent to those skilled in the art from the following detailed description of the invention and the accompanying drawings.